Dr. Naresh Punjabi is a promising young investigator who has made a substantial commitment to an academic career in clinical research. His commitment is evident in his pursuit of advanced clinical and research training, including completion of an residency in Internal Medicine, a fellowship in Pulmonary and Critical Care Medicine, and enrollment in the Graduate Training Program in Clinical Investigation at the Johns Hopkins University School of Hygiene and Public Health. This background provides a solid foundation for him to address challenging questions related to the diagnosis and management of sleep apnea, a pervasive problem with potentially significant consequences. Sleep apnea is one of the most common sleep disorders and is estimated to affect 18 million middle-aged adults in the United States. This disorder, which is especially prevalent in the elderly, is associated with hypertension, coronary artery disease, cognitive impairment, mood disturbances, diminished quality of life, and an increased risk for motor vehicle accidents. Despite the numerous effects of this disorder on health and society, a majority of affected individuals remain unrecognized. The proposed research in this application builds on Dr. Punjabi's previous research and addresses questions of fundamental importance related to the diagnosis and management of sleep apnea. The primary objective of this proposal is to develop and incorporate a risk-stratification approach for sleep apnea in clinical care. To this end, we propose three related studies: a) a retrospective study to develop a risk- stratification approach for sleep apnea using the clinical characteristics that are associated with an increased risk; b) a prospective validation study of this approach in a sleep-clinic and primary-care patient sample; and c) a randomized intervention trial to determine whether treatment is associated with improved patient outcomes. The principal investigator will also be strengthening his knowledge base in the methodology of clinical investigation in a supervised environment guided by exceptionally talented mentors. By combining the resources of the Johns Hopkins Medical Institutions and the practical experience in the pursuit of the outlined aims, the Mentored Patient-Orientated Research Career Development Award will provide Dr. Punjabi the opportunity to reach his full potential as a clinical investigator.